Removing all doubt: District Court interprets the phrase “discharges composed entirely of storm water”

Under the Clean Water Act and its implementing regulations, certain “discharges composed entirely of storm water,” including stormwater discharges associated with specified small construction activities and oil and gas and mining operations, do not require NPDES permits.  In order to qualify for these exemptions, however, these discharges must be “discharges composed entirely of storm water.”

I have always interpreted the phase “discharges composed entirely of storm water” to mean stormwater discharges that are not commingled with other varieties of discharges, as opposed to stormwater discharges that are free of any pollutants.  Because the phrase “discharges composed entirely of storm water” is never defined in the Clean Water Act or its implementing regulations, however, I have always possessed some small degree of doubt.

What if a court were to give the phrase “discharges composed entirely of storm water” its plain meaning?  Can discharges of stormwater that have picked up pollutants, like silt from a small construction site, nevertheless qualify as “discharges composed entirely of storm water?”  Can “discharges composed entirely of storm water” really include stormwater discharges that are composed of pollutants?  These are the kinds of questions that can keep an environmental lawyer up at night.

Late last month, the U.S. District Court for the Middle District of Pennsylvania put all doubts to rest.  The court held that a discharge is “composed entirely of storm water” even when it contains pollutants collected and conveyed solely as an incident to the collection and conveyance of stormwater.

In Gallagher v. East Buffalo Township, No. 4:12-cv-00777 (M.D. Pa. Memo. issued Aug. 29, 2013), a homeowner filed a complaint against a municipality alleging that a pipe and a ditch owned and maintained by the municipality as part of its stormwater management system discharges stormwater containing “sediment and other pollutants, including garbage, animal waste, and petroleum products,” onto her property and then into an unnamed tributary of the Susquehanna River.  The complaint included a claim under the citizen suit provision of the Clean Water Act in which the homeowner alleged that the municipality has violated and continues to violate the Clean Water Act by discharging pollutants from a point source to waters of the United States without a NPDES permit.

Among the “discharges composed entirely of storm water” that do not require NPDES permits under the Clean Water Act and its implementing regulations are stormwater discharges from certain small municipal separate storm sewer systems, or MS4s.  There was no dispute in Gallagher that the municipality operated a small MS4 whose stormwater discharges would not require a NPDES permit if they were “discharges composed entirely of storm water.”  The only real dispute was whether the stormwater discharges from this small MS4 were indeed “discharges composed entirely of storm water.”

The municipality argued that a stormwater discharge is “composed entirely of storm water” even when it “includes pollutants that are incidental to stormwater runoff.”  The homeowner, on the other hand, argued that the phrase “composed entirely of storm water” “means what it says, storm water, not pollutants.”  On cross-motions for summary judgment, the court sided with the municipality.

First, the court noted that the Clean Water Act only prohibits the discharge of pollutants from a point source without a NPDES permit.  Therefore, if “composed entirely of storm water” means “storm water, not pollutants,” no NPDES permit would be required for discharges “composed entirely of storm water” in the first place, so there would be no need for a permit exemption.  Because Congress created an exemption from the existing permit requirement for “discharges composed entirely of stormwater,” the court concluded that the legislature “must have contemplated that such discharges contained pollutants.”

Next, the court noted a provision of the Clean Water Act that requires a permit for a “discharge composed entirely of stormwater” where EPA determines that the discharge “contributes to a violation of a water quality standard or is a significant contributor of pollutants to waters of the United States.”  (The court noted a similar provision in the regulations that allows any person to petition EPA to require a NPDES permit for such a discharge.)  The court found that “it would be more than odd for Congress to have provided . . . that discharges that add no pollutants to the waters of the United States require a permit when they are significant contributors of pollutants to the waters of the United States.”

The court also noted a provision of the Clean Water Act that requires EPA to conduct a study for the purposes of “determining . . . the nature and extent of pollutants in [discharges composed entirely of stormwater].”  The court concluded that “it would be strange for Congress to have ordered the EPA to study . . . pollutant-free storm water discharges to determine ‘the nature and extent of pollutants in such discharges.'”

Finally, the court turned to legislative history, from which it divined that a major goal of the Water Quality Act of 1987, which created the exemption for “discharges composed entirely of stormwater,” was to substantially reduce stormwater-related permit applications.  Noting that “[p]ollutants are ubiquitous in storm water,” the court found it “hard to imagine legislators defining ‘discharges composed entirely of storm water’ as ‘storm water, not pollutants,’ when doing so would have undermined a major purpose of the [legislation].”

For reasons that I have previously explained here, I believe that it is entirely possible “that discharges that add no pollutants to the waters of the United States” might nevertheless “contribute[] to a violation of a water quality standard or [be] a significant contributor of pollutants to waters of the United States.”  Nevertheless, I would agree that Congress probably wasn’t contemplating high velocity stream flows that erode stream banks and stream beds when it enacted the Water Quality Act of 1987, and I find the reasoning that the court applied to reject a plain reading of “discharges composed entirely of storm water” to be sound.

The phrase “discharges composed entirely of storm water” does not mean what I suspect most of us never thought it meant.  We should all sleep a little bit better tonight.